(a) Field of the Invention
The present invention relates to a color filter composition.
(b) Description of the Related Art
Color filters are widely used in image sensing devices and in flat panel displays such as liquid crystal displays and organic electroluminescence devices, the application range for which has been rapidly widening.
The color filter used in a flat panel display or an image sensing device is typically manufactured by forming a pixel (emitter or sensor) of each primary color of red, green, and blue by repetitively forming a uniform coating of a colored photosensitive resin composition on a substrate including a black matrix. Each resin composition includes an appropriate pigment corresponding to each color, and the process is repeated to obtain the desired variety of colors. Subsequently, the coating layer is exposed and developed by primary baking (hereinafter referred to as heat drying or primary firing), and then, if necessary, by secondary baking (hereinafter referred to as a heat hardening or secondary firing).
In particular, liquid crystal displays for notebook PCs and mobile devices use color filters with high color purity and outstanding transmission characteristics. If a resin composition including the colored material has poor sensitivity to exposure, various defects due to generation of an undercut periphery may be generated. The undercut is caused by depth-dependent variation in the photohardening rate during the development process, such that the color filter material at the interface with the substrate develops more than the overlying layer.
To increase the composition's sensitivity to exposure, an initiator having an excellent photohardening property may be used and the concentration of the initiator may be increased. However, this method may increase the manufacturing cost, and causes a transmittance reduction due to the increased concentration of the initiator.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.